Lactobacillus is a genus of Gram-positive, facultative anaerobic or microaerophilic, rod-shaped, non-spore-forming bacteria. They are a major part of the lactic acid bacteria group (i.e. they convert sugars to lactic acid). In humans, they constitute a significant component of the microbiota at a number of body sites, such as the digestive system, urinary system, and genital system. In women of European ancestry, Lactobacillus species are normally a major part of the vaginal microbiota. Lactobacillus forms biofilms in the vaginal and gut microbiota, allowing them to persist during harsh environmental conditions and maintain ample populations. Lactobacillus exhibits a mutualistic relationship with the human body as it protects the host against potential invasions by pathogens, and in turn, the host provides a source of nutrients Lactobacillus is the most common probiotic found in food such as yogurt, and it is diverse in its application to maintain human well-being as it can help treat diarrhea, vaginal infections and skin disorders such as eczema

I hope link below is helpful

Article Importance of lactobacilli in food and feed biotechnology

Lactobacillus is a genus of Gram-positive, facultative anaerobic or microaerophilic, rod-shaped, non-spore-forming bacteria. They are a major part of the lactic acid bacteria group (i.e. they convert sugars to lactic acid). In humans, they constitute a significant component of the microbiota at a number of body sites, such as the digestive system, urinary system, and genital system. In women of European ancestry, Lactobacillus species are normally a major part of the vaginal microbiota. Lactobacillus forms biofilms in the vaginal and gut microbiota, allowing them to persist during harsh environmental conditions and maintain ample populations. Lactobacillus exhibits a mutualistic relationship with the human body as it protects the host against potential invasions by pathogens, and in turn, the host provides a source of nutrients Lactobacillus is the most common probiotic found in food such as yogurt, and it is diverse in its application to maintain human well-being as it can help treat diarrhea, vaginal infections and skin disorders such as eczema

i agree with Alaa Kareem Niamah and Lactobacillus is very helpfull bacteria that have food fermentative power and health promoting substance like a nisin-producing strain. most of ferme ted foods are due to the role of Lactobacillus

The term lacto infers the intimate association of this genus with milk, hence the long history of use of lactobacilli in manufacture of fermented dairy products.

https://medlineplus.gov/druginfo/natural/790.html

What is it?

Lactobacillus is a type of bacteria. There are lots of different species of lactobacillus. These are "friendly" bacteria that normally live in our digestive, urinary, and genital systems without causing disease. Lactobacillus is also in some fermented foods like yogurt and in dietary supplements.

Lactobacillus is taken by mouth to treat and prevent diarrhea, including infectious types such as rotaviral diarrhea in children and traveler's diarrhea. It is also taken by mouth to prevent and treat diarrhea associated with using antibiotics.

Some people take lactobacillus by mouth for general digestion problems, irritable bowel syndrome (IBS), colic in babies, inflammatory bowel disease (IBD), inflammation of the colon, too much bacterial growth in the intestines, constipation, to improve outcomes after bowel surgery, and to prevent a serious gut problem called necrotizing enterocolitis (NEC) in babies born prematurely. Lactobacillus is also taken by mouth for infection with Helicobacter pylori, the type of bacteria that causes ulcers, and also for other types of infections including urinary tract infections (UTIs), vaginal yeast infections, to prevent the common cold and flu, to prevent ear infections in children, and to prevent respiratory infections in children attending daycare centers and in children with cystic fibrosis. It is also taken by mouth for weight loss, rheumatoid arthritis, dental cavities, dental plaque, gum disease, and mouth sores. It is also being tested to prevent serious infections in people on ventilators.

Lactobacillus is taken by mouth for skin disorders such as fever blisters, canker sores, and acne. It is also used to treat or prevent eczema (allergic dermatitis), sensitivity to sun exposure (polymorphous light eruption), sensitivity to environmental allergens, and hay fever in infants and children.

It is also taken by mouth for high cholesterol, swine flu, HIV/AIDS, lactose intolerance, Lyme disease, hives, to prevent cancer, and to boost the immune system.

Women sometimes use lactobacillus suppositories to treat vaginal infections and urinary tract infections (UTIs).

How effective is it?

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, Ineffective, and Insufficient Evidence to Rate.

The effectiveness ratings for LACTOBACILLUS are as follows:

Likely effective for...

• Diarrhea in children caused by a certain virus (rotavirus). Children with rotaviral diarrhea who are being treated with Lactobacillus seem to get over their diarrhea about a half day earlier than they would without this treatment. Larger doses of lactobacillus are more effective than smaller ones. At least 10 billion colony-forming units during the first 48 hours should be used.

Possibly effective for...

• Hayfever. Taking two billion colony-forming units of Lactobacillus paracasei daily for 5 weeks can improve quality of life by almost 18% in people with grass pollen allergy that doesn't respond to the anti-allergy drug loratadine. Also, taking 10 billion colony-forming units of Lactobacillus johnsonii for 12 weeks seems to improve itchy eye symptoms in children with allergies that persist throughout the year.
• Preventing diarrhea caused by antibiotics. Research suggests that taking probiotics products containing only Lactobacillus strains reduces the risk of diarrhea caused by antibiotics. Also, giving children Lactobacillus GG (Culturelle) along with antibiotics seems to reduce diarrhea. There is conflicting evidence about the effects of Lactobacillus when taking together with other probiotics strains.
• Eczema (atopic dermatitis). Most research suggests that Lactobacillus products are beneficial for TREATING eczema. Lactobacillus GG seems to reduce symptoms of eczema in infants who are allergic to cow's milk. Lactobacillus sakei, Lactobacillus plantarum, and a combination of freeze-dried Lactobacillus rhamnosus and Lactobacillus reuteri also seem to reduce eczema symptoms in children ages 1 to 13 years. But Lactobacillus paracasei doesn't seem to be beneficial for treating eczema. Research on the effects of Lactobacillus for PREVENTING eczema is inconsistent. Some research suggests that taking Lactobacillus during pregnancy reduces the risk of eczema in infants. But other research suggests no benefit. This might be due to the strains of Lactobacillus used and how at risk the infants were for developing the skin condition.
• A condition associated with an increased risk for developing allergic reactions (atopic disease).. Research suggests that taking Lactobacillus might prevent the development of atopic disease, but only certain Lactobacillus strains seem to reduce the risk. A specific strain of Lactobacillus rhamnosus, Lactobacillus GG (Culturelle), taken by mouth 2-4 weeks before delivery and continued for the first three to six months of breast-feeding seems to prevent atopic disease (asthma, allergic rhinitis, and eczema) in infants with a family history of this condition. But other strains do not seem to have the same effect.
• Treating vaginal infections caused by bacteria (bacterial vaginosis). Clinical research shows certain strains of Lactobacillus might help treat bacterial vaginosis when applied inside the vagina. Researchers have found Lactobacillus acidophilus suppositories (Vivag, Pharma Vinci A/S, Denmark) and vaginal tablets (Gynoflor, Medinova, Switzerland) may be effective. Researchers have also found that vaginal capsules containing Lactobacillus gasseri and Lactobacillus rhamnosus (EcoVag Vaginal Capsules, Bifodan A/S, Denmark) can lengthen the time between infections. Eating yogurt containing Lactobacillus acidophilus might prevent these infections from occurring again.
• Preventing diarrhea due to cancer treatment (chemotherapy). A chemotherapy drug called 5-fluorouracil can cause severe diarrhea and other gastrointestinal (GI) side effects. There is some evidence that patients with cancer of the colon or rectum have less severe diarrhea, less stomach discomfort, shorter hospital care, and require fewer chemotherapy dose reductions due to GI side effects when they take a particular strain of Lactobacillus rhamnosus, Lactobacillus GG (Culturelle).
• Diarrhea. Giving a specific strain of Lactobacillus rhamnosus, Lactobacillus GG (Culturelle) to infants and children 1 to 36 months old when they are admitted to the hospital seems to reduce the risk developing diarrhea. Also, Lactobacillus GG can reduce the risk of diarrhea from all causes in undernourished children. But Lactobacillus GG does not seem to reduce how long otherwise healthy children experience diarrhea, suggesting that it might help prevent but not treat diarrhea. Some research suggests that consuming a specific product containing Lactobacillus casei (DanActive, Dannon) might help prevent diarrhea in children. But other research shows no preventative effect. A specific product containing Lactobacillus reuteri (BioGaia drops, BioGaia AB, Sweden) seems to help reduce the duration of diarrhea in children hospitalized with diarrhea.
• Helicobacter pylori (H pylori) infection. Research suggests that taking Lactobacillus can help treat stomach ulcers caused by H. pylori when taken along with "triple therapy" that consists of clarithromycin, amoxicillin, and a proton-pump inhibitor. It does not seem to help treat the infection when taken alone, with only an antibiotic, with other "triple therapies", or with "quadruple therapy" that includes bismuth.
• High cholesterol. Eating yogurt or taking capsules containing the Lactobacillus strain L. reuteri NCIMB 30242 (Cardioviva, Micropharma Limited) seems to reduce low-density lipoprotein (LDL or "bad") cholesterol by about 9% to 12% in adults with high cholesterol. Also, taking Lactobacillus plantarum also seems to reduce total cholesterol levels by 14% in adults with high cholesterol. But Lactobacillus does not seem to improve high-density lipoprotein (HDL or "good") cholesterol or triglycerides.
• Colic in babies. Taking a specific Lactobacillus reuteri product (Probiotic Drops, BioGaia AB) 100 million CFUs once daily for 21-28 days reduces daily crying time in nursing infants. Some research suggests that taking this Lactobacillus reuteri product seems to be more effective than using the drug simethicone. But a more recent study suggests that it does not reduce crying. It's possible that infants in the recent study had more severe colic than those in the earlier research.
• Treating irritable bowel syndrome (IBS). Research shows that Lactobacillus acidophilus can improve symptoms of IBS such as bloating and stomach pain. Lactobacillus plantarum 299v might also improve symptoms, but some conflicting results exists. Lactobacillus GG, Lactobacillus salivarius, and a combination of Lactobacillus paracasei, Lactobacillus acidophilus, and Bifidobacterium Bb12 don't seem to work.
• Inflamed mouth sores from cancer treatment (oral mucositis).Research suggests that taking lozenges containing Lactobacillus brevis from the first day of radiation/chemotherapy treatment until one week after reduces the number of patients who develop severe mouth sores.
• Inflammation of an artificial rectum surgically created in people with inflammatory bowel disease (pouchitis).Taking Lactobacillus by mouth seems to help treat pouchitis, a complication of surgery for ulcerative colitis. Taking a specific formulation of Lactobacillus, Bifidobacterium, and Streptococcus (VSL#3) for one year seems to maintain remission in 85% of people with this condition. Taking a different formulation containing two Lactobacillus species and Bifidobacterum for 9 months seems to reduce pouchitis severity.
• Lung infections. Children ages 1 to 6 years who attend daycare centers seem to get fewer and less severe lung infections when given milk containing Lactobacillus GG or a specific combination product containing both Lactobacillus acidophilus and Bifidobacterium (HOWARU Protect).
• Rheumatoid arthritis (RA). Research shows that taking a specific strain of Lactobacillus casei for 8 weeks reduces tender and swollen joints in women with rheumatoid arthritis.
• Preventing diarrhea due to traveling. Traveler's diarrhea is caused by bacteria, viruses, or parasites that the traveler has not been exposed to before. Taking a specific strain of Lactobacillus rhamnosus, Lactobacillus GG (Culturelle) seems to help prevent diarrhea in travelers. The effectiveness of Lactobacillus GG can vary a lot depending on the travel destination because of differences in bacteria in different locations.
• Treating a bowel condition called ulcerative colitis.. Some research suggests that taking a specific combination product containing Lactobacillus, Bifidobacterium, and Streptococcus (VSL#3) might improve symptoms in people with ulcerative colitis. Continuous treatment for one year seems to help most patients. Taking another specific product containing Lactobacillus plantarum 299v (Profermin, Nordisk Rebalance) also seem to improve symptoms.

Possibly ineffective for...

• Treating diarrhea caused by the bacterium Clostridium difficile. Research suggests that taking Lactobacillus GG is not effective for the prevention of Clostridium difficile diarrhea. Taking other Lactobacillus species, including Lactobacillus casei Shirota, Lactobacillus acidophilus, and other strains of Lactobacillus rhamnosus, also does not appear to be effective for preventing Clostridium difficile infections when taken with antibiotics.
• Crohn's disease. Some research shows that taking specific strains of Lactobacillus rhamnosus, Lactobacillus GG (Culturelle) and Lactobacillus johnsonii does not seem to prevent Crohn's disease from coming back after surgery.
• Dental plaque. Giving Lactobacillus reuteri to mothers starting 4 weeks before delivery until birth, and then continuing in the infants until 12 months of age, does not seem to reduce dental plaque in the baby teeth of the child by the age of 9 years.
• Necrotizing enterocolitis (NEC) in babies born prematurely. Lactobacillus GG does not seem to prevent necrotizing enterocolitis in very small babies. Also, giving Lactobacillus reuteri or a specific product containing a combination of Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus plantarum, Bifidobacterium infantis, and Streptococcus thermophilus (Laboratorio Italmex SA, Mexico City, Mexico) to very small infants does not reduce the risk of death or NEC.
• Ear infection. Research suggests that taking a specific formula (NAN 3 formula, Nestle Baby) containing Streptococcus thermophiles, Streptococcus salivarius, and Lactobacillus rhamnosus, together with the prebiotics raftilose and raftiline for 12 months, does not reduce the risk of ear infections in healthy infants.
• Vaginal yeast infections after taking antibiotics. There is evidence that taking Lactobacillus by mouth or eating yogurt enriched with Lactobacillus doesn't prevent vaginal yeast infections after antibiotics. However, women with yeast infections who use vaginal suppositories containing 1 billion live Lactobacillus GG bacteria twice daily for 7 days in combination with conventional treatment often report their symptoms improve.

Insufficient evidence to rate effectiveness for...

• Acne. Taking Lactobacillus and other probiotics by mouth together with antibiotics might improve acne. Early research shows that taking a specific product containing Lactobacillus acidophilus, Lactobacillus bulgaricus, and Bifidobacterium bifidum (Trenev Trio/Healthy Trinity, Natren, Westlake Village, CA) twice daily along with minocycline once daily in the evening for 12 weeks improves acne.
• Common cold. Early research suggests that taking Lactobacillus plantarum and Lactobacillus paracasei daily for 12 weeks might reduce the risk of common cold by about 12% and reduce the number of days with symptoms from 8.6 to 6.2 in adults. Also, taking a combination of Lactobacillus acidophilus and Bifodobacterium for 3 months seems to reduce school absences due to cold symptoms. However, research is inconsistent. Taking Lactobacillus helveticus daily for 6 weeks does not seem to reduce the number of cold/flu days in otherwise healthy adult students. Also drinking a beverage containing Lactobacillus brevis does not seem to reduce the risk of catching a cold.
• Constipation. Lactobacillus might reduce constipation when taken in combination with other probiotics. But not all combinations help. Taking specific products (Hexbio or Lactofos), which contain fructooligosaccharide, Lactobacillus, and Bifidobacterium, reduces constipation in adults. But eating a yogurt containing polydextrose, Lactobacillus acidophilus, and Bifidobacterium lactis does not reduce constipation. The effects of Lactobacillus alone are unclear.
• Cystic fibrosis. Research suggests that taking Lactobacillus reuteri daily for 6 months reduces the percentage of cystic fibrosis patients with lung complications from 37% to 3% and the percentage with upper respiratory tract infections from 20% to 3%.
• Dental cavities. Research on the effects of Lactobacillus on dental cavities is mixed. Giving Lactobacillus reuteri to mothers starting 4 weeks before delivery until birth, and then continuing in the infants until 12 months of age, seems to reduce cavities in the child's baby teeth. But giving infants a cereal containing Lactobacillus paracasei (Semper AB, Stockholm, Sweden) from 4 months until 13 months of age does not reduce cavities in baby or permanent teeth.
• Stomach pain. Early research suggests that taking Lactobacillus reuteri twice daily for 4 weeks can reduce the severity but not frequency of stomach pain in children 6 to 16 years-old. Other early research suggests that taking Lactobacillus acidophilus and Bifidobacterium lactis twice daily for 30 days improve stomach pain.
• Flu. Taking a probiotic test drink (Kagome, Nagoya, Japan) containing Lactobacillus brevis five days weekly for 8 weeks reduces the incidence of the flu in schoolchildren during flu season. But taking Lactobacillus helveticus daily for 6 weeks does not seem to reduce the number of cold/flu days in otherwise healthy adults.
• Lactose intolerance. Research on the effects of lactobacillus on lactose intolerance is conflicting. Some research shows that drinking Lactobacillus acidophilus milk produces the same symptoms of intolerance as regular cow's milk in people with lactose intolerance. But other research shows that drinking a milk product containing Lactobacillus bulgaricus reduces symptoms of lactose intolerance.
• Skin rash caused by sun exposure (polymorphous light eruption). Early research suggests that taking a supplement containing Lactobacillus johnsonii and other ingredients (Inneov Sun Sensitivity, Laboratoires Innéov, Asnières sur Seine, France) daily for 12 weeks reduces the severity ofskin reactions after sun exposure in people with polymorphous light eruption.
• Growth of bacteria in the intestines. Some clinical research has evaluated lactobacillus for treating and preventing growth of potentially harmful bacteria in the intestines. Some of this research shows modest improvements in symptoms of stomach pain, bloating, and diarrhea; however, other research has found no benefit in people with bacterial overgrowth. Lactobacillus does not seem to be helpful for preventing growth of harmful bacteria in the intestines.
• Urinary tract infections (UTIs). There is some early evidence that vaginal use of some Lactobacillus species might be helpful for preventing UTIs, but not all studies have agreed. There is also conflicting evidence about the effects of taking Lactobacillus by mouth.
• Pneumonia in people on breathing machines in the hospital. Early research suggests that taking Lactobacillus rhamnosus GG (Culturelle) twice daily might reduce the incidence of pneumonia in people in the intensive care unit.
• Weight loss. Research suggests that taking Lactobacillus rhamnosus twice daily for 24 weeks does not reduce body weight or fat mass in obese adults. But when only considering its effects in women, Lactobacillus rhamnosus does seem to reduce body weight.

The link might help https://medlineplus.gov/druginfo/natural/790.html

https://en.wikipedia.org/wiki/Lactobacillus

best info about it, I am sure it will helps you alot

actobacillus is a genus of Gram-positive, facultative anaerobic or microaerophilic, rod-shaped, non-spore-forming bacteria.They are a major part of the lactic acid bacteria group (i.e., they convert sugars to lactic acid). In humans, they constitute a significant component of the microbiota at a number of body sites, such as the digestive system, urinary system, and genital system. In women of European ancestry, Lactobacillus species are normally a major part of the vaginal microbiota.Lactobacillus forms biofilms in the vaginal and gut microbiota, allowing them to persist during harsh environmental conditions and maintain ample populations.Lactobacillus exhibits a mutualistic relationship with the human body, as it protects the host against potential invasions by pathogens, and in turn, the host provides a source of nutrients.Lactobacillus is the most common probiotic found in food such as yogurt, and it is diverse in its application to maintain human well-being, as it can help treat diarrhea, vaginal infections, and skin disorders such as eczema

Please take a look at this useful link.

http://www.imedpub.com/articles/lactobacilli-as-probiotics-and-their-isolation-from-different-sources.pdf