Viability,Acid and Bile Tolerance of Spray Dried Probiotic Bacteria and Some Commercial Probiotic Supplement Products Kept at Room Temperature

Production of probiotic food supplements that are shelf‐stable at room temperature has been developed for consumer's convenience, but information on the stability in acid and bile environment is still scarce. Viability and acid and bile tolerance of microencapsulated Bifidobacterium spp. and Lactobacillus acidophilus and 4 commercial probiotic supplements were evaluated. Bifidobacterium and L. acidophilus were encapsulated with casein‐based emulsion using spray drying. Water activity (a_w) of the microspheres containing Bifidobacterium or L. acidophilus (SD GM product) was adjusted to 0.07 followed by storage at 25 °C for 10 wk. Encapsulated Bifidobacterium spp. and Lactobacillus acidophilus and 4 commercial probiotic supplement products (AL, GH, RE, and BM) were tested. Since commercial probiotic products contained mixed bacteria, selective media MRS‐LP (containing L‐cysteine and Na‐propionate) and MRS‐clindamycin agar were used to grow Bifidobacterium spp. or L. acidophilus, respectively, and to inhibit the growth of other strains. The results showed that a_w had a strong negative correlation with the viability of dehydrated probiotics of the 6 products. Viable counts of Bifidobacterium spp. and L. acidophilus of SD GM, AL, and GH were between 8.3 and 9.2 log CFU/g, whereas that of BM and RE were between 6.7 and 7.3 log CFU/g. Bifidobacterium in SD GM, in AL, and in GH products and L. acidophilus in SD GM, in AL, and in BM products demonstrated high tolerance to acid. Most of dehydrated probiotic bacteria were able to survive in bile environment except L. acidophilus in RE product. Exposure to gastric juice influenced bacterial survivability in subsequent bile environment.     

Effect of packaging materials and dissolved oxygen on the survival of probiotic bacteria in yoghurt

The effects of packaging materials on the dissolved oxygen and the survival of the probiotic bacteria in yoghurt were studied. Oxygen adapted and non‐oxygen adapted strains of Lactobacillus acidophilus and Bifidobacterium spp. were incorporated in yoghurts, which were packaged in oxygen permeable high‐impact polystyrene (HIPS), oxygen‐barrier material (Nupak^TM) and Nupak^TM with an oxygen scavenging film (Zero₂^TM). During storage the dissolved oxygen increased steadily in HIPS packaged yoghurt whereas it remained low in yoghurts packaged in Nupak^TM and Zero₂^TM. In all yoghurts, no significant decreases were observed in the viability of either oxygen adapted or non‐oxygen adapted cells of L. acidophilus and Bifidobacterium spp. Thus, although the dissolved oxygen in yoghurt can be influenced by the type of packaging material, it may not affect the survival of probiotic bacteria in yoghurts.     

Enhancing the Biotransformation of Isoflavones in Soymilk Supplemented with Lactose Using Probiotic Bacteria during Extended Fermentation

ABSTRACT: Soymilk (SM) lacks lactose; hence supplementation of SM with lactose is likely to enhance the growth of probiotic bacteria and biotransformation of isoflavone glycosides to isoflavone aglycones. In this study, 11 strains of probiotic bacteria including Lactobacillus rhamnosus, L. salivarius, L. plantarum, L. acidophilus, L. paracasei, HOWARU L. rhamnosus, L. delbrueckii subsp. bulgaricus, Bifidobacterium lactis type Bi-07, B. longum, HOWARU B. bifidum, and B lactis type Bi-04 were inoculated individually or as mixed cultures into SM and soymilk supplemented with lactose (SML). A total of 2% of lactose was added to 1 L of SM with the aim of improving the growth of probiotic organisms and promoting the biotransformation of isoflavone isomers to bioactive isoflavone aglycomes. Samples of SM were incubated at 37 °C and 10 mL aliquots of SM were taken at 0, 24, 48, and 72 h to monitor the growth of probiotic bacteria and changes in isoflavone contents using high-performance liquid chromatography (HPLC). Results indicated that SML fermented with probiotics had higher viable counts by >2.4 log CFU/mL than that in SM at the end of the 72 h fermentation period. Mixed cultures grew at different rates and in general Lactobacilius spp. had >1.02 log CFU/mL more cells than Bifidobacterium spp. at the end of the fermentation period. The total aglycone content in SM at 72 h of fermentation was 0.924 mg/100 mL, whereas that in SML was 1.623 mg/100 mL. Addition of lactose not only improved the growth of probiotic bacteria in SM but also enhanced the biotransformation of isoflavone glucosides to the more bioactive isoflavone aglycones. Mixed cultures did not improve the biotransformation of bioactive isoflavones when compared to single cultures.     

Probiotic bacteria: selective enumeration and survival in dairy foods

A number of health benefits have been claimed for probiotic bacteria such as Lactobacillus acidophilus, Bifidobacterium spp., and Lactobacillus casei. Because of the potential health benefits, these organisms are increasingly incorporated into dairy foods. However, studies have shown low viability of probiotics in market preparations. In order to assess viability of probiotic bacteria, it is important to have a working method for selective enumeration of these probiotic bacteria. Viability of probiotic bacteria is important in order to provide health benefits. Viability of probiotic bacteria can be improved by appropriate selection of acid and bile resistant strains, use of oxygen impermeable containers, two-step fermentation, micro-encapsulation, stress adaptation, incorporation of micronutrients such as peptides and amino acids and by sonication of yogurt bacteria. This review will cover selective enumeration and survival of probiotic bacteria in dairy foods.     

Probiotic Bacillus spp. in Soy‐Curd: Nutritional,Rheological, Sensory,and Antioxidant Properties

The focus of this study was to coculture probiotic Bacillus spp. with dairy starter cultures namely, Streptococcus thermophilus and Lactobacillus bulgaricus for enhanced nutritional properties of soy‐curd. Subsequently, rheological, sensory, and antioxidant properties of soy‐curd along with mineral as well as fatty acid composition were analyzed. Data revealed an increase in the cell viability of probiotic Bacillus spp. on coculturing rather than as mono‐culture. Proximate analysis showed higher nutritional value along with increased trace elements. UFA/SFA ratio, rheology, and sensory properties of probiotic soy‐curd were in the acceptable range. Probiotic soy‐curd showed higher antioxidant activity as measured by the ability to scavenge free radicals. No significant difference in the overall quality within the probiotic products was observed. However, B. flexus MCC2427 cocultured product displayed slightly better attributes than other samples. In general, the results suggest that soy‐curd can be a suitable carrier for probiotic Bacillus spp. and the enhanced nutritional and antioxidant properties could be of additional advantage to combat malnutrition problem.     

Survival of probiotic adjunct cultures in cheese and challenges in their enumeration using selective media

Various selective media for enumerating probiotic and cheese cultures were screened, with 6 media then used to study survival of probiotic bacteria in full-fat and low-fat Cheddar cheese. Commercial strains of Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus paracasei, or Bifidobacterium lactis were added as probiotic adjuncts. The selective media, designed to promote growth of certain lactic acid bacteria (LAB) over others or to differentiate between LAB, were used to detect individual LAB types during cheese storage. Commercial strains of Lactococcus, Lactobacillus, and Bifidobacterium spp. were initially screened on the 6 selective media along with nonstarter LAB (NSLAB) isolates. The microbial flora of the cheeses was analyzed during 9 mo of storage at 6°C. Many NSLAB were able to grow on media presumed selective for Lactococcus, Bifidobacterium spp., or Lb. acidophilus, which became apparent after 90 d of cheese storage, Between 90 and 120 d of storage, bacterial counts changed on media selective for Bifidobacterium spp., suggesting growth of NSLAB. Appearance of NSLAB on Lb. casei selective media [de man, Rogosa, and Sharpe (MRS) + vancomycin] occurred sooner (30 d) in low-fat cheese than in full-fat control cheeses. Differentiation between NSLAB and Lactococcus was achieved by counting after 18 to 24 h when the NSLAB colonies were only pinpoint in size. Growth of NSLAB on the various selective media during aging means that probiotic adjunct cultures added during cheesemaking can only be enumerated with confidence on selective media for up to 3 or 4 mo. After this time, growth of NSLAB obfuscates enumeration of probiotic adjuncts. When adjunct Lb. casei or Lb. paracasei cultures are added during cheesemaking, they appear to remain at high numbers for a long time (9 mo) when counted on MRS + vancomycin medium, but a reasonable probability exists that they have been overtaken by NSLAB, which also grow readily on this medium. Enumeration using multiple selective media can provide insight into whether it is the actual adjunct culture or a NSLAB strain that is being enumerated.     

Dried Tomato‐Flavored Probiotic Cream Cheese with Lactobacillus paracasei

Abstract: A dried tomato‐flavored probiotic cream cheese (P) containing Lactobacillus paracasei Lpc‐37 was developed for the purpose of this study. The same product, but without probiotic addition (C) was used as control. Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris were used as lactic starter cultures. Chemical composition analyses and sensory tests were performed on days 1 and 7, respectively. Titratable acidity, pH value and L. paracasei population were determined every 7 d during the refrigerated storage (21 d) of the cream cheeses. The experiment and analyses were performed in triplicate, using standard methods. Probiotic population remained greater than 10⁷ CFU/g throughout the storage period, thereby characterizing the product as potentially probiotic. Cream cheeses C and P did not differ on the sensory tests, both obtaining good overall acceptance by the consumers, of which 82.6% stated that they certainly or probably would buy the product. Practical Application: Lactobacillus paracasei Lpc‐37 is a probiotic bacterium and clinical studies have shown that this microorganism beneficially affects its host. In general, dried tomato‐flavored products and cream cheese are products with good acceptance by the consumers. Thus, regular consumption of the probiotic cream cheese developed in this study may have positive effects on health and well being of people if incorporated into their diet.     

Physiochemical Properties,Microstructure, and Probiotic Survivability of Nonfat Goats’ Milk Yogurt Using Heat‐Treated Whey Protein Concentrate as Fat Replacer

There is a market demand for nonfat fermented goats’ milk products. A nonfat goats’ milk yogurt containing probiotics (Lactobacillus acidophilus, and Bifidobacterium spp.) was developed using heat‐treated whey protein concentrate (HWPC) as a fat replacer and pectin as a thickening agent. Yogurts containing untreated whey protein concentrate (WPC) and pectin, and the one with only pectin were also prepared. Skim cows’ milk yogurt with pectin was also made as a control. The yogurts were analyzed for chemical composition, water holding capacity (syneresis), microstructure, changes in pH and viscosity, mold, yeast and coliform counts, and probiotic survivability during storage at 4 °C for 10 wk. The results showed that the nonfat goats’ milk yogurt made with 1.2% HWPC (WPC solution heated at 85 °C for 30 min at pH 8.5) and 0.35% pectin had significantly higher viscosity (P < 0.01) than any of the other yogurts and lower syneresis than the goats’ yogurt with only pectin (P < 0.01). Viscosity and pH of all the yogurt samples did not change much throughout storage. Bifidobacterium spp. remained stable and was above 10⁶CFU g^‐1 during the 10‐wk storage. However, the population of Lactobacillus acidophilus dropped to below 10⁶CFU g^‐1 after 2 wk of storage. Microstructure analysis of the nonfat goats’ milk yogurt by scanning electron microscopy revealed that HWPC interacted with casein micelles to form a relatively compact network in the yogurt gel. The results indicated that HWPC could be used as a fat replacer for improving the consistency of nonfat goats’ milk yogurt and other similar products.     

Functional cultures and health benefits

A number of health benefits have been claimed for probiotic bacteria such as Lactobacillus acidophilus, Bifidobacterium spp., and L. casei. These benefits include antimutagenic effects, anticarcinogenic properties, improvement in lactose metabolism, reduction in serum cholesterol, and immune system stimulation. Because of the potential health benefits, these organisms are increasingly being incorporated into dairy foods, particularly yoghurt. In addition to yoghurt, fermented functional foods with health benefits based on bioactive peptides released by probiotic organisms, including Evolus^® and Calpis^®, have been introduced in the market. To maximize effectiveness of bifidus products, prebiotics are used in probiotic foods. Synbiotics are products that contain both prebiotics and probiotics.     

Whey protein isolate- and carrageenan-based edible films as carriers of different probiotic bacteria

The use of polymer blends as carriers for probiotic cells or using multi-strain probiotic culture mixture in film formulations has a high potential to maintain the stability of probiotics throughout storage. In this study, the survival of Lactobacillus acidophilus, Lactobacillus plantarum, and mixed culture (Lactobacillus spp., Lactococcus spp., and Bifidobacterium spp.) in whey protein isolate (W), carrageenan (C), and W/C blend (W to C on a wt/wt basis at 100 to 0, 75 to 25, 50 to 50, and 0 to 100) films were investigated during 30 d of storage at 4 and 25°C. The water vapor, mechanical, optical, and morphological properties of film samples were also determined. A significant decrease in total lactic acid bacteria counts of all strains (5–6 log cfu/g in reduction) for W and C films was observed during storage at 25°C, whereas blended films had 2 to 3 log cfu/g reduction. The mixed culture-incorporated films had higher cell counts during all storage temperatures. The incorporation of probiotic bacteria significantly influenced the water vapor permeability and color values of films while decreasing tensile strength and elongation at break values. This study reveals that a multi-strain mixed culture presented more chance for survival inside the polymer matrix, especially when carbohydrate- and protein-based polymers were blended.     

In vitro fermentation of cereal dietary fibre carbohydrates by probiotic and intestinal bacteria

A range of probiotic and other intestinal bacteria were examined for their ability to ferment the dietary fibre carbohydrates β‐glucan, xylan, xylo‐oligosaccharides (XOS) and arabinoxylan. β‐Glucan was fermented by Bacteroides spp and Clostridium beijerinckii but was not fermented by lactobacilli, bifidobacteria, enterococci or Escherichia coli. Unsubstituted xylan was not fermented by any of the probiotic bacteria examined. However, many Bifidobacterium species and Lactobacillus brevis were able to grow to high yields using XOS. XOS were also efficiently fermented by some Bacteroides isolates but not by E coli, enterococci, Clostridium difficile, Clostridium perfringens or by the majority of intestinal Lactobacillus species examined. Bifidobacterium longum strains were able to grow well using arabinoxylan as the sole carbon source. These organisms hydrolysed and fermented the arabinosyl residues from arabinoxylan but did not substantially utilise the xylan backbone of the polysaccharide. Arabinoxylan was not fermented by lactobacilli, enterococci, E coli, C perfringens or C difficile and has potential to be an applicable carbohydrate to complement probiotic Bif longum strains in synbiotic combinations. © 2002 Society of Chemical Industry     

Bioprotection of Ready‐to‐eat Probiotic Artichokes Processed with Lactobacillus paracasei LMGP22043 against Foodborne Pathogens

The survival of 3 pathogens Listeria monocytogenes ATCC19115, Salmonella enterica subsp. enterica ATCC13311, and Escherichia coli ATCC8739 was evaluated over time in ready‐to‐eat (RTE) artichoke products processed or not with the probiotic strain Lactobacillus paracasei LMGP22043. Both probiotic and standard products (final pH about 4.0; a_w = 0.98) dressed with oil and packaged in modified atmosphere were inoculated with pathogens at a level of about 3 log CFU/g and stored at 4 ºC for 45 d. Pathogens decreased in the probiotic product in 2 descent phases, without shoulder and/or tailing as observed by fitting the models available in the GInaFit software to the experimental data. S. enterica subsp. enterica was completely inactivated after 14 and 28 d in probiotic and standard products, respectively; E. coli was inhibited in the probiotic food at day 4 (count <detection limit (DL) 1 log CFU/g), while in the standard product, it survived until the end of experiment. L. monocytogenes decreased in the probiotic product at day 1 reaching values below the DL after 14 d, while 21 d were needed in the standard product, and survived in both samples until the end of the experimental period. Therefore, the probiotic strain, representing always more than the 93% of lactic acid bacteria (about 7 log CFU/g) during the entire experimental period, combines the efficacy of a protective culture, which can control the development of pathogens during storage with probiotic benefits.     

Improving the Stability of Probiotic Bacteria in Model Fruit Juices Using Vitamins and Antioxidants

Abstract: This study examined the survival of probiotic bacteria in a model fruit juice system. Three different strains of probiotic bacteria were used in this study: HOWARU Lactobacillus rhamnosus HN001, HOWARU Bifidobacterium lactis HN001, and Lactobacillus paracasei LPC 37. The probiotic bacteria were inoculated into model juice with various vitamins and antioxidants, namely white grape seed extract, green tea extract, vitamin B2, vitamin B3, vitamin B6, vitamin C, and vitamin E. The model juice without any additives was used as a control. Their viability was assessed on a weekly basis using plate count method. The model juice was made with sucrose, sodium citrate, citric acid powder, and distilled water and was pasteurized before use. Our findings showed that probiotic bacteria did not survive well in the harsh environment of the model fruit juice. However, the model juice containing vitamin C, grape extract, and green tea extract showed better survival of probiotic bacteria. The model juice containing grape seed extract, green tea extract, and vitamin C had the same initial population of 8.32 log CFU/mL, and at the end of the 6-wk storage period it had an average viability of 4.29 log CFU/mL, 7.41 log CFU/mL, and 6.44 log CFU/mL, respectively. Juices containing all other ingredients tested had viable counts of <10 CFU/mL at the end of the 6-wk storage period.     

Performance in Nondairy Drinks of Probiotic L. casei Strains Usually Employed in Dairy Products

The increase in vegetarianism as dietary habit and the increased allergy episodes against dairy proteins fuel the demand for probiotics in nondairy products. Lactose intolerance and the cholesterol content of dairy products can also be considered two additional reasons why some consumers are looking for probiotics in other foods. We aimed at determining cell viability in nondairy drinks and resistance to simulated gastric digestion of commercial probiotic lactobacilli commonly used in dairy products. Lactobacillus casei LC‐01 and L. casei BGP 93 were added to different commercial nondairy drinks and viability and resistance to simulated gastric digestion (pH 2.5, 90 min, 37 °C) were monitored along storage (5 and 20 °C). For both strains, at least one nondairy drink was found to offer cell counts around 7 log orders until the end of the storage period. Changes in resistance to simulated gastric digestion were observed as well. Commercial probiotic cultures of L. casei can be added to commercial fruit juices after a carefull selection of the product that warrants cell viability. The resistance to simulated gastric digestion is an easy‐to‐apply in vitro tool that may contribute to product characterization and may help in the choice of the food matrix when no changes in cell viability are observed along storage. Sensorial evaluation is mandatory before marketing since the product type and storage conditions might influence the sensorial properties of the product due to the possibility of growth and lactic acid production by probiotic bacteria.     

Evaluation of Probiotic Potential of Lactic Acid Bacteria Isolated from Different Sources in Western India

Lactic acid bacteria isolated from unconventional sources are often attractive targets in the quest for obtaining better probiotics. In the present study, 16 members of the genus Lactobacillus, isolated from 3 different sources in western India, viz., plants, fermented foods and beverages, and human feces, were evaluated for their probiotic and bioactive properties. The isolates were closely related to Lactobacillus fermentum, Lactobacillus pentosus, and mainly Lactobacillus plantarum. The isolates were tolerant to bile salt, acidic pH and pancreatin, although pancreatin tolerance was generally low. Cellular extracts of several isolates displayed antioxidant activity, while cell-free supernatants displayed antibacterial activity against human pathogens. Antioxidant activity of Lactobacilli of human origin was higher than those from vegetables or fermented foods and beverages. L. plantarum AG40V prevented spoilage of fresh-cut fruits, vegetables and sprouted mung-beans. Lactobacilli from all sources displayed equal probiotic potential and those of human origin displayed superior antioxidant activity over others.     

Incorporation of Propionibacterium shermanii subsp. freudenreichii in probiotic dairy drink production: physicochemical,rheological, microbiological and sensorial properties

The aim of this study was to investigate the use of Propionibacterium shermanii subsp. freudenreichii as a combined culture with Lactobacillus acidophilus (AP), Bifidobacterium animalis subsp. lactis (BP), Lactobacillus casei (CP) and Lactobacillus rhamnosus (RP) in probiotic dairy drink production. Although Propionibacterium spp. is used for many purposes including biopreservative and adjunct culture, in this study, probiotic dairy drinks containing P. freudenreichii were evaluated in terms of their physicochemical, rheological, microbiological and sensory properties. The results of the study showed that P. freudenreichii can also be suitable for the production of probiotic drinks and that there are no adverse effects on the product characteristics.     

Structural Stability and Viability of Microencapsulated Probiotic Bacteria: A Review

Probiotics are live microorganisms that confer a number of health benefits when consumed in adequate amounts, mostly due to improvement of intestinal microflora. Bacterial strains from the genera Lactobacillus, Bifidobacterium, and Bacillus have been widely studied and are used to prepare ready‐to‐eat foods. However, the physicochemical stability and bioavailability of these bacteria have represented a challenge for many years, particularly in nonrefrigerated foodstuffs. Microencapsulation (ME) helps to improve the survival of these bacteria because it protects them from harsh conditions, such as high temperature, pH, or salinity, during the preparation of a final food product and its gastrointestinal passage. The most common coating materials used in the ME of probiotics are ionic polysaccharides, microbial exopolysaccharides, and milk proteins, which exhibit different physicochemical features as well as mucoadhesion. Structurally, the survival of improved bacteria depends on the quantity and strength of the functional groups located in the bacterial cell walls, coating materials, and cross‐linkers. However, studies addressing the role of these interacting groups and the resulting metabolic impacts are still scarce. The fate of new probiotic‐based products for the 21st century depends on the correct selection of the bacterial strain, coating material, preparation technique, and food vehicle, which are all briefly reviewed in this article.     

Mixed Cultures of Food-grade Probiotic Bacteria and Enteric Bacteria Demonstrate Both Synergism and Inhibition of Menaquinone Production

ABSTRACT: The interaction between probiotic ( Enterococcus spp., Lactobacillus spp., and Lactococcus spp.) and enteric ( Bacteroides spp., Escherichia coli , and Salmonella spp.) bacteria with respect to menaquinone production was examined. Menaquinones were measured in cell pellets by high-pressure liquid chromatography and the main homologues produced were MIK_7–11. The growth of both Bacteroides and E. coli cultured with the 3 probiotics was significantly inhibited with concomitant reduction in menaquinone production. The vitamin K status of humans could be affected by consumption of probiotic dairy foods via the contribution made by gut microflora.     

Performance of Commercial Cultures in Fluid Milk Applications

Six Lactobacillus acidophilus, 5 Bifidobacterium, and 6 Streptococcus thermophilus strains were studied for characteristics that are important to activity and stability in unfermented fluid milk products. Speciation, strain relatedness, frozen concentrate stability, bile sensitivity, and lactase activity were evaluated. The microbiological stability of a culture-containing fluid milk product was also determined. Two of the bifidobacteria cultures contained >1 strain. Some strains were shown to be closely related or identical by pulsed-field gel electrophoresis of fragmented chromosomal DNA. Selective media that distinguished among all 3 added genera were identified. All lactobacilli and most of the bifidobacteria were resistant to bile concentrations varying from 1 to 3%, and all streptococci were sensitive to bile. Lactase activities were highest for S. thermophilus strains, supporting use of this species in fluid milk and dairy products to aid in the digestion of lactose by consumers. The experimental product evaluated in this study contained 10⁷ cfu/ml of both L. acidophilus and Bifidobacterium spp. and 5 × 10⁷ cfu/ml of S. thermophilus. Lactic, but not psychrotrophic, populations were fairly stable during storage. The results suggest that milk formulated with high concentrations of three different genera of probiotic bacteria can be manufactured with commercial strains.     

蜂粮中Lactobacillus kunkeei的益生特性研究

蜂粮是植物花粉、蜂蜜和蜜蜂唾液的发酵混合物,是营养丰富的天然食材。作者从蜂粮中分离到61株乳酸杆菌,经16S rRNA基因测序,鉴定为Lactobacillus kunkeei。首先,用邻苯二甲醛法对61株L.kunkeei进行胆固醇去除能力检测,其中5株菌胆固醇去除能力均大于15%,菌株B35对胆固醇的去除率达到(29.07±1.30)%。随后,对这5株L.kunkeei进行酸耐受性、胆盐耐受性、抗生素耐药性及抑菌等益生特性进行研究。耐酸实验和耐胆盐实验结果表明,5株L.kunkeei均具有良好的耐酸性和胆盐耐受性。药敏试验结果表明,5株L.kunkeei对4种临床常用抗生素(红霉素、克林霉素、庆大霉素、万古霉素)均敏感。通过琼脂扩散法抑菌实验,发现5株L.kunkeei对大肠埃希氏菌、金黄色葡萄球菌均有一定的抑菌作用。B35菌株的细胞黏附性能良好,对Caco-2细胞的黏附率达到3.32%。从蜂粮中分离到5株具有良好益生特性的菌株,其中菌株B35的益生特性最佳,为益生菌的开发与利用提供了新的菌种资源。